Typewriting machine



Apri125, 1939. RGTHOMPSON 2,155,999

TYPEWRITING MACHINE Filed Sept. 4, 1936 (Eil ATTORN EY Patented Apr. 25,1939 UNITED STATES PATENT OFFICE TYPEWRITING MACHINE ApplicationSeptember 4, 1936, Serial No. 99,378

3 Claims.

This invention relates to typewriting machines, and especially todevices for supporting and securing such machines in a manner to reducethe noise resulting from their operation.

Much of the noise incident to the use of typewriting machines resultsfrom the magnification of the sounds of the operating mechanism byreason of the transmission of such so-unds, in themselves small, throughthe machine-frame to the desk or working surface on which the machinerests, said surface actingv as a sounding board, with a resultingmagnifying effect.

Rubber or other resilient mountings, comprising cushions of variouskinds and intended to insulate against such transmission, are wellknown. The common characteristic of these prior devices, however, isthat the resilient material is under compression, resulting in anobviously inefficient structure, because the immediate increase indensity increases the sound and vibration transmission qualities of thematerial. In addition, the constant pounding to which a typewriter issubjected during use has the cumulative effect of so distorting andcompacting the resilient material as to render it absolutely valuelessas an insulator in a comparatively short time.

These disadvantages are overcome in this invention, in which theresilient material is placed under tension, thus lessening its densityand increasing the insulating value, and continued use, up to areasonable limit, acts actually to improve the insulating qualities.

In viewof the foregoing, a general object of the invention is to providean improved mount or foot for typewriters and like machines, of simpleand inexpensive construction and elfective to substantially prevent thetransmission of operating noises from the machine to the desk platformor other structure upon which the machine rests.

Other objects and advantages will hereinafter appear.

In the drawing, Figure 1 is a fragmentary side elevational view of atypewriter mounted on a desk platform, the mount or foot being shown incentral section, and

Figure 2 is a perspective view of the typewriter foot.

A typewriter 3 has its frame 4 formed to receive a set of four feet 5,the frame 4 having a series of holes, each threaded to receive a screw 6for attachment of the typewriter feet thereto. In use the typewriter isusually positioned on the desk platform or table 'I which may be a partof the usual secretarial desk wherein the typewriter carrying platformis swingably mounted to the desk in the well known manner so that bytilting the platform, the typewriter is concealed within the desk whennot in use. Y

The screw 6 may have a cylindrical head 8 hav- `5 ing a slot therein toreceive a screw driver bit for attaching the foot 5 to the typewriter.The screw head 8 fits snugly but removably in a cylindrical collar 9having at its upper end an inturned rim I6 overlying the shoulder of thescrew and adapt- 10 ed to be clamped between the screw head 8 and thetypewriter frame 4. The cylindrical collar 9 constitutes the bodyportion of an inner member of the typewriter foot and has at its lowerend an l outwardly projecting bottom flange II disposed l5 substantiallynormal to the axis of the screw 6. The typewriter foot also includes anouter member having a cylindrical wall I 2 at the top of which is aninwardly projecting flange I 3l overl lying the ange Il of the innermember, the 2b ange I3 having a central aperture through which the bodyportion 9 projects so that the typewriter is spaced from the top flangeof the outer member. The cylindrical wall I 2 of the outer memberextends substantially below the bottom 25 of flange II and is adapted torest directly upon the platform 1, the wall I2 having an outwardlydirected flange I4 providing a broad area for contact with the platform.A

It is to be noted that the respective flanges II, 30 I3 match and are inparallelism with each other, as are also the cylindrical wall I2 and thebody portion 9. A resilient rubber ring I6 is interposed between theinner and outer foot members, being secured as by vulcanizing to theconfronting faces 35 of the said members. That is, the rubber ring I6 isvulcanized to both the iianges I I and I3, and to the outer surface ofthe collar 9 and the inner surface of the cylindrical wall I2 of theouter member. o

At the outer margin of the bottom of rubber ring I6 is an integral beador annular portionl 2| disposed between the periphery of the bottomflange II and the wall I2 to keep these members from actualmetal-to-metal contact. A similar 45 bead 22 is provided at the top ofthe ring IB, being disposed within the inner edge of the top ange II andthe body portion 9.

Under load of the typewriter, the inner member is pressed downwardly andtends to further 50 separate the flanges II and I3 thus causing astretching or tensioning of the rubber ring I6. The arrangement of theflanges II, I3 with their confronting faces substantially matching eachother, and being secured to the rubber ring I6 55 entirely over thesematching faces, assures that the entire ring I6 be subjected to thetensioning stress imparted by the load of the typewriter. The ring I6,being under tension, vhas a greater vibration absorbing effect than weresame put under a shearing or compression stress. The inner member of thetypewriter foot is thus suspended, by the rubber ring I6, on the outermember and may move downwardly under the load of the typewriter or toabsorb any vibrations occurring therein, to prevent transmission ofthese vibrations to the platform 1. The rubber beads- 2|, 22, althoughpermitting any necessary downward movement of the inner member, preventsame from moving excessively in a lateral direction, thereby providing arelatively flrm but yieldable support for the typewriter.

The outer ange I4 of each typewriter foot may, in coaction with otherdevices secured to the platform 'I, serve to maintain the position oftheltypewriter on the platform. As shown herein, `ametal plate I'I maybe of ample size as to underlie substantially the entire area of thetypewriter and is secured to the platform 1 by screws I8. A felt mat I9is interposed between the plate I'I and the platform 'I and is effectivein dampening sound vibrations emanating from the typewriter. The plateI'I has peripheral portions 2U overlapping a part of the flange I4 ofthe typewriter foot and coacts therewith to hold the typewriter in placeon the platform during operation or, when the typewriter is tilted intothe desk.

Variations may be resorted to within the scope of the invention, andportions of the improvements may be used without others.

Having thus described my invention, I claim:

1. A resilient foot for support of a typewriter on a platform.,comprising in combination, an inner member having a cylindrical bodyportion adapted for attachment to the typewriter and a flange projectingoutwardly from the bottom thereof substantially at right angle to theaxis of said body portion, an outer member having a cylindrical wallembracing said inner member and having an inwardly projecting top angeoverlying and matching the flange of said inner member in parallelismtherewith, and a resilient ring interposed between said inner member andsaid outer member and vulcanized to the confronting faces of said innerand outer members,

- the body portion of said inner member reaching above said top flangeand the cylindrical wall of said outer member reaching below the flangeof said inner member and being restable on a platform, to permit saidresilient ring to tension freely under load of the typewriter.

2. A resilient foot for support of a typewriter on a platform,comprising in combination, an inner member having a hollow cylindricalbody portion adapted to removably receive a shouldered screw therein forattachment of the foot to a typewriter, said body portion having aninturned rim for clamping between the screw shoulder and the typewriter,said inner member having a flange projecting outwardly from the bottomthereof, an outer member having a, cylindrical wall embracing said innermember and having an inwardly projecting top flange overlying andmatching the bottom flange of said inner member in parallelismtherewith, and a resilient rubber Aring interposed between said innerand outer members vulcanized to substantially the entire confrontingfaces of said inner and outer members, the body portion of said innermember reaching above said top flange and the cylindrical wall of saidouter member reaching below the flange of said inner member and beingrestable on a platform, to permit said resilient ring to tension freelyunder load of the typewriter.

3. A resilient foot for support of a typewriter on a platform,comprising in combination, an inner member having a cylindrical bodyportion adapted for attachment to a typewriter and a flange projectingoutwardly from the bottom thereof substantially at right angle to theaxis of said body portion, an outer member having a cylindrical wallembracing said inner member and having an inwardly projecting top flangeoverlying and matching the bottom flange of said inner member inparallelism therewith, and a resilient rubber ring vulcanized to theconfronting faces of said inner and outer members, said resilient ringhaving an upper annular portion between the body of said inner memberand the edge' of the top ange and having a bottom annular portionbetween the edge of the flange of said inner member and the wall of saidouter member, the body portion of said inner member reaching above saidtop flange and the cylindrical wall of said outerI member reaching belowthe ilange of said inner member and being restable on a platform, topermit said resilient ring to tenl sion freely under load of thetypewriter.

RUSSELL G. THOMPSON.

